Water-cooled Heat Recovery DC Inverter VRF
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(1) IDU/ODU rated capacity collocation ratio C = Sum of rated cooling capacity of indoor unit / Sum of rated
cooling capacity of outdoor unit.
(2) If all of the indoor units are fresh air indoor units, the quantity of refrigerant added to each module is 0kg.
(3) If outdoor air processor is connected with normal VRF indoor unit, adopt the perfusion method for normal
indoor unit for perfusion.
Example1:
The OUD is composed of the module: 120 kBtu/h.
The IDUs are made up of 4 sets of 30 kBtu/h.
IDU/ODU rated capacity collocation ratio C= 30×4/(120)=100%.The quantity of included IDUs is
more than 4 sets. Please refer to the above table.
Refrigerant charging amount B for 120 kBtu/h module is 3.0kg (6.6pounds).
So, Refrigerant charging amount B =3kg (6.6pounds).
Suppose the P
ipeline charging amount A=Σ Liquid pipe length × refrigerant charging amount of
every 1m (39.37in.) liquid pipe=2kg (4.4 pounds).
Total refrigerant charging amount R=2+3=5kg (4.4+6.6=11pounds).
Example 2:
Outdoor unit is a 72kBtu/h module and the indoor unit is a 72kBtu/h fresh air unit. The quantity (B)
of refrigerant added to this module is 0kg (0pounds).
As a result, Refrigerant charging amount B = 0kg (0pounds).
Suppose the Pipeline charging amount A =
Σ Length of liquid pipe x Quantity of refrigerant added
to liquid pipe per meter) = 5kg (11pounds).
Total refrigerant charging amount R = 5+0=5kg (11+0=11pounds).
After confirmed there is no leakage from system, when the compressor does not operates,
charge additional R410A with specified amount to the unit through the fluorine injection nozzles at the
outdoor liquid pipe valve of the outdoor unit. If required additional refrigerant cannot be quickly
charged due to pressure increase inside the pipes, turn on the unit at cooling mode and then charge
the refrigerant from low pressure gas valve of outdoor unit. If water inlet temperature is low, the unit
can’t be set to cooling mode, but heating mode, which is also accepted.
4.5.3 Precautions on Refrigerant Leakage
(1) Personnel related to air conditioning engineering design and installation should abide by the
safety requirement for preventing refrigerant leakage specified in local laws and regulations.
(2) The units apply R410A refrigerant, which is nonflammable and nontoxic. However, the
space for refrigerant leakage should be large enough to ensure the refrigerant concentration
does not exceed the specified value in safety requirement; otherwise, people inside the
space will be dangerous of stifled by refrigerant. For example, according to the appropriate
European Standard, the maximum allowable concentration level of R410A to human space
is limited at 0.44 kg/m³.
The maximum amount of refrigerant (kg) in the system = The volume of room (m
3
) ×The
maximum allowed concentration level of refrigerant (kg/m³).
Total amount of refrigerant (kg) in the system = Total additional charging amount (kg) + Amount
Summary of Contents for GMV-WQ120WM/A-F
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